I am trying to understand the true color differences, and would really appreciate someone posting some relatively closely graded IH cents in Red, Brown and RB so I can see some color variations. Thank you very much in advance!
I don't have anything in stock that'll answer your question cleanly, but PCGS has (what I consider) a pretty good comparison at CoinFacts on the 1864-L: http://www.pcgscoinfacts.com/Coin/Detail/2079 ....and 1909-S pages: http://www.pcgscoinfacts.com/Coin/Detail/2239 One caveat: the color calibration on your own monitor may not match the one they (or any photographer whose images you're examining) have in front of them. You may not see exactly what they see.
I have quite a few cents that were graded RD that absolutely are NOT any more, two of them might not even make RB any more, they're BR if any ever is. Cents CAN AND DO tone quite a bit inside a slab. In fact, they can tone FASTER than raw cents in the same environment.